Add a listener to communicate with a test.

If EVENT_FILE_ROBOLECTRIC exist, create AtestRunListener to inform atest about test status.

Bug: 124421998

Test: source build/envsetup.sh ; lunch
      m atest && atest-dev RunStorageManagerRoboTests RunBluetoothRoboTests

Change-Id: I9b8f9d4df6e1d9b68f642ac1060755db5c6f34d8